[FIX] note: fix _notification_recipients

Since revision 458aaca328,
the `groups` args of the method `_notification_recipients`
is a list of tuple, and no longer a dict.

The code here has not been adapted to this change.
It is now.

opw-695300

addons/note/models/note.py

@@ -126,7 +126,9 @@ class Note(models.Model):
         groups = super(Note, self)._notification_recipients(message, groups)
         new_action_id = self.env['ir.model.data'].xmlid_to_res_id('note.action_note_note')
         new_action = self._notification_link_helper('new', action_id=new_action_id)
-        groups['user']['actions'] = [{'url': new_action, 'title': _('New Note')}]
+        for group, method, kwargs in groups:
+            if group == 'user':
+                kwargs.setdefault('actions', []).append({'url': new_action, 'title': _('New Note')})
         return groups
 
     @api.multi